A pool of cells known as stem cells located in the center of the shoot apical meristem (SAM) are responsible to maintain meristematic activity throughout a plants life in order to produce organs. The maintenance of these stem cells is tightly controlled by a complex genetic and hormonal network. Any disruption that leads to the loss of stem cells will end the formation of new plant organs and therefore the plants life-cycle. The balance between leaf initiation and meristem maintenance is controlled by internal and external factors, although our knowledge about the nature of these factors is very limited. This thesis reports the results of a study on SAM loss in tomato and brassica and the genetic and environmental factors causing this arrest. The aim was to study which environmental conditions could lead to so-called blind tomato and brassica plants and to develop a method that could induce this phenomenon. Furthermore, a genomic region responsible for blindness in brassica was identified.